﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Numerics;
using System.Text;
using System.Threading.Tasks;

namespace _10_CalculatingFactorial
{
    class Program
    {
        private static void FactorialCalculation(int n)
        {
            BigInteger factorial = 1;

            for (int index = 1; index <= n; index++)
            {
                factorial *= index;
            }

            Console.WriteLine("{0}! = {1}", n, factorial);
        }

        static void Main()
        {
            int n = int.Parse(Console.ReadLine());

            FactorialCalculation(n);
        }
    }
}